lakes, rivers, streams, and groundwater
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Lakes, Rivers, Streams, and Groundwater
Aquifers/ groundwater
Principal Watershed Components
Lakes Rivers/Streams
Swamps/WetlandsSoils
Hydrologic Connections
The Florida Example
Precambian 4.5 Bya to 500 Mya
Paleozoic 500 Mya to 248 Mya
Mesozoic 248 Mya to 65 Mya
Cenozoic 65 Mya to present
Geologic Time Line
(Earth formation, cooling, oceans, atmosphere, life, oxygen)
Approximately 250 million years ago
Rifting phase
- 250 Mya
Breakup of PangaeaLate Triassic, early Jurassic
Approximately 150 - 200 million years ago
Flooded, stable platformfor marine sedimentation
FL platform/plateau
For the next several million years the platform was dominated by carbonate deposition
Late Jurassic
High Sea Levels
Carbonate Deposition
Marine Calcium and Magnesium Carbonate
CaCO3
MgCO3
Florida platform was a flooded, submarineplateau dominated by carbonate deposition
FL platform
CaCO3
Between about 150 Mya and 25 Mya
Raised above earth’s crust
Dominated by carbonates
Formed over millions of years
Gently sloping
The Florida Platform
Cenozoic EraPaleocene Eocene Oligocene Miocene Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA 5.3-1.8 1.8 MY – 10KYA
carbonates
Before Miocene
Late Oligocene-Early MiocenePaleocene Eocene Oligocene Miocene Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA 5.3-1.8 1.8 MY – 10KYA
Suwannee Current
Georgia Channel
Late Oligocene-Early MiocenePaleocene Eocene Oligocene Miocene Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA 5.3-1.8 1.8 MY – 10KYA
Events:
•Lifting of the Florida Platform
•Lowering of Sea Levels, diversion of the Gulf Stream, interruption of Suwannee Current
•Rejuvenation of Appalachians, increased sediment load
•Filling of Georgia Channel
•Rising sea levels, lack of Suwannee Current
•Continental depositional influence on Fl. platform
Late Oligocene-Early MiocenePaleocene Eocene Oligocene Miocene Pliocene Pliestocene
66-58 MYA 58-37 MYA 37-24 MYA 24-5.3 MYA 5.3-1.8 1.8 MY – 10KYA
Suwannee Current
Georgia Channel
sediments
Siliciclastic Deposition
silici- refers to a chemical composition rich in silicate material
clastic- refers to the origin of the particles as clasts, products or fragments of silicate rocks.
Typical earth materialsSilicon-based sands, silts,
clays, rocks, rock fragments
Sands
Limestone
sands, silts, clays, rock 25 to 5 Mya
Miocene deposits are siliciclastic: sands, silts, clays, rocks
Megalodon #MG1Locality: Hawthorne Formation, South Carolina
Age:MioceneSize: 6 inches exactly
Virtually flawless museum grade specimen. Perfect serrations, black and gray mottlingPrice: $785.00 SOLD
Miocene sediments are marine sediments
In Gainesville, Miocene clays tend to be fairly thick and, in many cases, close to the surface
Alfred A. Ring Park
1801 NW 23rd Boulevard—parking at Elks Lodge
The thickness of and depth to Miocene sediments varies
Up to 40% phosphorus
0-500 ft thick in the North-central part of state
Also contains uranium
Thin or absent
30 – 200 ft sandy
30 – 200 ft clayey
> 200 ft thick
Alachua CountySediment Thickness
Thinning Miocene Sediments
Jurassic To
Miocene
Miocene
The thickness of the Miocene sediments hasA direct bearing on the formation of springs and sinkholes
Carbonate Dissolution
Acid (H+) dissolves calcium carbonate
Marine Carbonates
Miocene Siliciclastics
Limestone Cavities
Directly underlies Miocene deposits
Miocene Siliciclastics
Sinkholes
Solution (sinkhole) lakes
The most common origin of lake formation in Florida
Limestone bedrock is dissolved by acids
Land subsidence into dissolvedlimestone cavity createsdepressions filled with water
Sinkhole Lakes
Lakes are hydrologically connected to each otherAnd with the underlying aquifer system
Springs
Springs form best when the overlying clay layer is thin.
Calcareous streams
originate from springs
colder temperatures
clear water
rich in calcium and phosphorus
Santa FeIchetuckneeWeeki Wachee
Direct hydrologic connectionwith the carbonate aquifer
Hydrologic Connections
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